CN106663079B

CN106663079B - Management device for managing errors on universal serial bus

Info

Publication number: CN106663079B
Application number: CN201580037860.5A
Authority: CN
Inventors: M·阿贾杰; A·布瓦瑟里
Original assignee: Peugeot Citroen Automobiles SA
Current assignee: PSA Automobiles SA
Priority date: 2014-07-11
Filing date: 2015-07-02
Publication date: 2020-11-06
Anticipated expiration: 2035-07-02
Also published as: EP3167379B1; FR3023633A1; EP3167379A1; FR3023633B1; WO2016005683A1; CN106663079A

Abstract

The invention relates to an electronic equipment comprising a host controller capable of controlling at least one universal serial communication port capable of being connected to a plurality of peripheral devices, characterized in that each of the peripheral devices connected to said port is associated with a peripheral monitor (27), said peripheral monitor (27) being capable of determining and indicating a communication failure between said port and the peripheral device associated with said peripheral monitor, and in that said host controller comprises means for reinitializing said communication port when all the peripheral monitors indicate a communication failure.

Description

Management device for managing errors on universal serial bus

Technical Field

The present invention relates to data transmission over a serial bus, and more particularly to error management during transmission.

Background

The Universal Serial Bus (or USB for short in english "Universal Serial Bus") is a Serial transmission information Bus for connecting a peripheral information device (also referred to as "USB devices" in english) to a computer (also referred to as a host or "USB host" in english).

USB evolves into multiple versions, each of which is capable of communicating in multiple modes.

The first version of the USB bus communicates in two modes: slow mode (or "Low Speed", flow 1.5Mbit/s) or Full Speed mode (or "Full Speed", flow 12 Mbit/s):

the second version of the USB bus also includes a third mode (referred to as "High Speed" with traffic of 480 Mbit/s).

The USB bus operates based on a Token Ring (or "Token Ring") by which each network node is arranged in turn on the bus.

Bandwidth is shared in time among all connected peripherals. During the time that multiple transmissions can occur, the time is subdivided into multiple frames or micro-frames.

Communication between the host and the peripheral device is performed according to a protocol based on the sequential interrogation of each peripheral device by the host. When a host wishes to communicate with a peripheral device, the host sends a token (a data packet containing the address of the peripheral device, the address being encoded with seven bits) representing the peripheral device. If the peripheral device identifies the address of the peripheral device in the token, the peripheral device sends a data packet in return.

USB defines different types of transmission: control transfers (for enumeration and configuration of peripheral devices), interrupt transfers (for providing small amounts of information with small reaction times), isochronous transfers, and bulk transfers (for transferring large amounts of information).

Communications between the host and the peripheral device can be structured into multiple logical channels (pipes and endpoints) to simplify control of the peripheral device to the USB port.

USB does not define a means to easily manage transmission errors. For example, for a U disk where there is a music library connected to the player, if a brief physical malfunction (vibration, shock, or other) occurs on the wiring harness, the player is no longer able to play subsequent music, which is paused.

The user is thus forced to disconnect the usb-disk and reconnect the usb-disk to reinitialize the communication, or to restart the music player.

A method and a system for controlling a USB coupling are known from document US 2006/0236003. However, this solution is not able to overcome transmission errors.

Disclosure of Invention

It is therefore an object of the present invention to overcome the above problems. To this end, the invention proposes more precisely an electronic equipment comprising a host able to control at least one universal serial communication port able to be connected to a plurality of peripheral devices, characterized in that each of the peripheral devices connected to the communication port is associated with a peripheral monitor able to determine and indicate a communication failure between the communication port and the peripheral device associated with the peripheral monitor, and in that the host comprises means to reinitialize the communication port when all the peripheral monitors indicate a communication failure.

In the event of a communication failure with all peripheral devices, the present invention can disable the USB port to obtain a savings in power consumption.

Advantageously, the means for re-initializing the communication port is a finite state automaton.

Advantageously, the finite state automaton comprises at least three states:

an initialization state corresponding to an initialization of a communication between the host and the peripheral device,

-a nominal state corresponding to a communication with nominal traffic between the host and the peripheral device.

-a peripheral error state, the peripheral error state corresponding to a communication failure between the host and the peripheral.

Advantageously, the finite state automaton further comprises a degraded state corresponding to a communication having degraded traffic between the host and the peripheral, the degraded traffic being less than the nominal traffic.

By setting the degraded state, the present invention is able to establish degraded mode communication when a failure occurs, rather than losing communication.

Advantageously, the finite state automaton further comprises an error state, the error state corresponding to a communication failure between the host and all peripheral devices connected to the host.

This feature enables easy implementation of the disabling of the USB port in case of communication failure with all peripheral devices.

Advantageously, the finite state automaton switches from the nominal state to the degraded state after detecting a communication failure between the host and the peripheral device.

Advantageously, the finite state automaton switches from the degraded state to the peripheral error state after detecting a communication failure between the host and the peripheral.

Advantageously, the finite state automaton switches from the degraded state to the nominal state after the first predetermined condition is fulfilled.

This enables, for example, a communication with degraded traffic to be re-established with nominal traffic after a predetermined time in degraded mode.

Advantageously, the finite state automaton switches from the peripheral error state to the degraded state after the second predetermined condition is fulfilled.

This enables, for example, reestablishing the interrupted communication with degraded traffic after a predetermined time after the interruption of the communication, without requiring intervention by the user.

The invention also relates to a vehicle comprising an arrangement according to the invention.

Drawings

Other features and advantages of the present invention will become more apparent upon reading the following detailed description and the accompanying drawings, in which:

figure 1 shows a schematic diagram of a network;

fig. 2 shows a schematic diagram of an automaton, which illustrates the operation of the monitor according to the invention.

Detailed Description

The drawings may not only serve to supplement the invention but also to help define it, if necessary.

Fig. 1 shows a schematic diagram of a network. The network couples the host 11 with the first peripheral device 12 and with the second peripheral device 13 by means of USB couplings.

In this example, the number of peripheral devices is limited to two. But the number of peripheral devices of the network may vary without departing from the scope of the invention.

In the following, as a non-limiting example, the host 11 is considered to be a computer of a motor vehicle. The invention is not limited to this embodiment. Indeed, the present invention relates to any computer that includes a USB connector and a USB host controller.

In the following, as a non-limiting example, the first peripheral device 12 is considered to be also a computer of a motor vehicle. The invention is not limited to this embodiment. In fact, the present invention relates to any computer that includes a USB connector and a USB peripheral device controller.

The second peripheral device 13 is for example a peripheral storage device (of the hard disk type).

Referring to fig. 2, the monitor 20 is a robot that includes the following states:

"sleep" 21, USB low-level is not initialized;

- "initialize" 22: the USB lower layer is initialized and waits for the connection of the peripheral device 12;

- "nominal": functional USB communication of high-speed traffic between host 11 and peripheral 12;

- "degradation": functional USB communication of full speed traffic between host 11 and peripheral 12;

- "error _ x": communication with peripheral device 12 is disabled;

- "error": and all peripheral devices 12, 13 connected to the USB port of the host 11 are disabled. The USB port is disabled.

Note that seven layers are typically distinguished in the communication model ("physical", "data link", "network", "transport", "session", "presentation" and "application"). The first three layers are referred to as hardware layers or lower layers, while the last four layers are referred to as upper layers or upper layers.

The "sleep" state 21 corresponds to a non-functional USB network. After the host 11 is powered on, the monitor 20 of the USB network is in a "sleep" state 21.

When the upper software layer needs to use the USB network, the monitor 20 transitions to the "initialize" state 22. This state corresponds to the initialization of the lower layers of the USB network.

Therefore, the monitor 20 is set to wait for the connection of the USB peripheral device 12.

When the USB peripheral device 12 is detected, the monitor 20 transitions to a "nominal" state 23.

Upon entering the "nominal" state 23, the supervisor 20 initializes communications with the USB peripheral device 12 to have nominal traffic.

In the event of a failure, monitor 20 transitions to a "degraded" state.

Conversely, if the communication is properly established with nominal flow, the monitor 20 remains in the "nominal" state 23.

If a network failure (e.g., a loss of communication) occurs while the host 11 is in the "nominal" state 23, the network monitor 20 transitions to the "degraded" state 24.

In the "degraded" state 24, the monitor 20 initializes communications with the peripheral device 12 to have degraded traffic.

In the event of a failure, the monitor transitions to the "ERROR _ X" state 25.

If the communication is properly established with degraded traffic, peripheral device 12 remains in a "degraded" state 25.

If a network failure (e.g., a communication loss) occurs while the host 11 is in the degraded state 24, the network monitor 20 transitions to the ERROR _ X state 25.

In the "error _ x" state 25, the connection to the peripheral device 12 is disabled and no communication between the host 11 and the peripheral device 12 is possible.

The "initialization", "nominal", "downgrade" and "error x" states are combined in a "sub automaton" 27, which is referred to as a peripheral monitor that only involves a single peripheral.

The network monitor 20 needs to implement the status of as many peripheral monitors 27 as there are peripheral devices connected to the USB port.

When all peripherals are declared to be in the "error _ x" state (in other words, when all peripheral monitors 27 are in the "error _ x" state 25), the monitor 20 transitions to the "error" state 26. In this state, the host 11 disables the USB port.

In a variant embodiment of the invention, when the monitor 20 transitions to the "error" state 26, this "error" state causes the USB lower layer to reinitialize and then to transition to the "initialization" state 22.

When the upper software layer no longer needs to use the USB network, the monitor 20 transitions to the "sleep" state 21 regardless of the connection state between the host and the peripheral devices 12, 13.

According to an embodiment variant of the invention, the network monitor 20 transitions to the "nominal" state 23 when the host 11 is in the "degraded" state 24 and after the conditions are fulfilled (for example after a predetermined time has elapsed).

According to an embodiment variant of the invention, the network monitor 20 transitions to the "degraded" state 24 when the host 11 is in the "error _ x" state and after the condition is fulfilled (for example after a predetermined time has elapsed).

Claims

1. An electronic equipment comprising a host (11) capable of controlling at least one universal serial communication port connectable to a plurality of peripheral devices (12, 13), characterized in that each of the peripheral devices (12, 13) connected to the communication port is associated with a respective peripheral monitor (27), the peripheral monitor (27) being capable of determining and indicating a communication failure between the communication port and a single peripheral device associated with the peripheral monitor, the communication failure being a loss of communication, and in that the host (11) comprises means for re-initializing the communication port when all peripheral monitors indicate a communication failure.

2. Electronic equipment according to claim 1, characterized in that the means to reinitialize the communication port is a finite state automaton (20).

3. Electronic equipment according to claim 2, characterized in that the finite state automaton (20) comprises at least three states:

an initialization state (22) corresponding to the initialization of a communication between the host (11) and the peripheral device (12),

-a nominal state (23) corresponding to a communication with a nominal traffic between the host (11) and the peripheral device (12),

-a peripheral error state (25) corresponding to a communication failure between the host (11) and the peripheral (12).

4. The electronic equipment of claim 3, wherein the finite state automaton further comprises a degraded state (24) corresponding to a communication having a degraded traffic between the host (11) and the peripheral device (12), the degraded traffic being less than a nominal traffic.

5. Electronic equipment according to any of claims 2 to 4, characterized in that the finite state automaton (20) further comprises an error state (26) corresponding to a communication failure between the host (11) and all peripheral devices (12, 13) connected to the host (11).

6. Electronic equipment according to claim 4, characterized in that the finite state automaton (20) switches from the nominal state (23) to the degraded state (24) after detection of a communication failure between the host (11) and the peripheral device.

7. Electronic equipment according to claim 4, characterized in that the finite state automaton (20) switches from the degraded state (24) to the peripheral error state (25) after detection of a communication failure between the host (11) and the peripheral.

8. Electronic equipment according to claim 4, characterized in that the finite state automaton (20) switches from the degraded state (24) to the nominal state (23) after the first predetermined condition is fulfilled.

9. Electronic equipment according to claim 4, characterized in that the finite state automaton (20) switches from the peripheral error state (25) to the degraded state (24) after the second predetermined condition is fulfilled.

10. A vehicle comprising the electronic equipment of any one of claims 1-9.